NO rx audio on a Galaxy dx959

[Shoebox223]

No rx audio, has rx signal,new audio ic. Heard this radio has had audio issues. Tx audio good,roger beep good. Any ideas...thanks

[RedEye]

Does PA audio work? If not check for 8 volts at the mic circuit board. I had one that the transistor went south....

[Shoebox223]

Thanks Redeye for the response...Had 8 volts at mic board, Changed audio IC again,now it has rx audio but severely choked back.Any other tips? Thanks again

[Rick]

Thanks Redeye for the response...Had 8 volts at mic board, Changed audio IC again,now it has rx audio but severely choked back.Any other tips? Thanks again

but severely choked back.Any other tips?
What does this mean

Rick.

[Shoebox223]

Sorry...should have said sounds like it's slightly distorted and very low in audio

[Rick]

Change all the electrolytic capacitors around the audio chip, C175, C179, C180, C181 and C182 and make shore you put the new ones in the right way round.

Rick.

[Shoebox223]

Replaced the 5 caps...still no good

[Rick]

Is the PA working?

Rick.

[Shoebox223]

Yes the P.A. works. Volume control works but has very low audio. Has 8V at mic board. Almost as though the input to the audio ic is weak. Help!! Thanks again

[Rick]

Can you hear the squelch open and closeing when you rotate the squelch control?

The next think you need to do is find if you have good audio at connect (J5) pin 2 which is a brown wire, you need a small headphone (Pocket radio type) connect one wire from the headphone to pin 2 brown wire and connect the second to Pin 3 which is a red wire, switch the 959 on and is if you can near the audio nice and clear. Let us know how you get on.

Rick

[Shoebox223]

yes...audio is clear

[Shoebox223]

Yes the squelch works also

[Rick]

Try the same test as before but this time put one of the wires from you headphone to Pin 4 on the audio chip and put the second wire to ground one of the coils tin cans will do, let us know how you get on. Also can give me list of the voltages at all the pins of the audio chip. Is the Talk back working?.

Rick.

[Shoebox223]

Thanks again Rick for your time....no audio present at pin 4.
audio IC voltages:
pin 1 13.2
2 6.4
3 0
4 0
5 1.2
6 1.2
7 0
8 0
9 6.6
10 12.5

[Rick]

The voltages you gave me are ok.

Ok now we are get some where, you now need to check at component level, first connect one wire of your headphone to ground and connect the other one to one side of R231 which is a 10K resistor and see if you can hear any sound if not with one wire still connect to ground connect other one to plug J5 pin 1 and see if you can hear any sound. Also is the Talk back working?.

Rick.

[Shoebox223]

Has very very weak audio at r231 and at pin 1 of J5....about the same as whats coming out of speaker. P.A. works

[Rick]

Ok it looks like you have one of two faults. First try shorting Pins 1 and 2 of J5 together this is the Black wire and the Brown on J5. if this does not work try removing transistor Q44 (2SC945) near R231.

Rick.

[Shoebox223]

Shorting pins 1 and 2 did the trick!!!!

[Rick]

The next think to do is remove the front the radio so you can get at the front panel circuit control board, once you have the control board out check the NF board this is the one in front of connecter J15, check all the solder joints and let me know if the NF board has been removed.

Rick.

[Shoebox223]

Touched up some solder joints....looks like the NF board has never been touched

[Shoebox223]

Has audio at pin 2....no audio at pin 4

[Rick]

Ok then if you look at front panel circuit control board can you see where the NF board should be?

Rick.

[Shoebox223]

NF board is there

[Rick]

Ok the NF board are known to give problems, it is best to remove it and solder a link from the second pin down to the four pin down using J16 the pin Nearest to J16 Red wire is pin 1, 2,3 ,4 and so on. Can you follow this ok? that should be job done.

Rick.

[Shoebox223]

Many Many thanks Rick....your a genius!!!! Aligning radio now....was a free radio and thought it was worth taking a look at.Thanks again

Doug

[Rick]

OK glad I could be of some help. It makes a change to help some one that does as one suggested. You can find the Aligning data on http://www.cbtricks.com/

Rick.

[222]

for rick: well, i already screwed this up once...don't know where the unfinished post i composed disappeared to, but here goes tryin again...hope i've got this posted in the right place...sorry if not. i stumbled onto this forum while searching for help on a similar type of problem. i read & was impressed w/how you handled & solved the issue for shoebox 223 on his 959. i hope you have enough time to help w/this one...i have a cobra 2000 gtl w/etremely low (approx. 5-10%) rx audio level. rx signal ok...squelch seems ok...tx audio fine...still have to go back to check pa audio...problem same regardless of internal/ext. spkr, or sp1/2 jacks...checked for intermittents...audio ic, & transistors, etc. in vicinity, all seem to be running cool...have a schematic, but it doesn't identify transistor purposes, nor do i have a block diagram. i had hoped those might have helped point me to some recieve audio amps, associated caps, or something along those lines. would appreciate any help, ideas, direction...
222

[Shoebox223]

If Rick can't help you resolve the problem...chances are it can't be fixed.He is the best!

[smokinone]

I'm a little late in the conversation, but having the same problem When I move the NF board the receive audio lowers, then gains. Is the NF board removed and discarded, then the jumpers installed, or jumper then put the NF board back in?
Thanks.
Also with the same radio, I have replaced the finals, and the audio chip 7222. Also have done an alignment. Problem is I have good audio in talkback, and good audio in PA, but when transmitting, audio is garbled or indiscernible. I have about 15-20 watts plus SSB out according to my meter, I haven't tried the AM audio but I was not able to make contacts on SSB although I had folks telling me they heard me, just couldn't understand my transmission. PLL and Transmit alignment is where it is supposed to be.
I might add this is a MOSFET radio, had no output until the new finals. I was thinking of replaceing the Q54 & 55, but the voltages are correct. Before I bought it someone had cut the audio wire from the mic board to put in a noise toy I think. I soldered it back together. The guy I bought it from had one for sale anyway, and this was a parts radio. No channels, clarifier is stock and as far as I can tell no modifications. Q39 was removed, and I replaced that with a new one.
Thanks in advance for the help.

[Shoebox223]

I removed the NF board

[222]

What is the "NF board referred to in this thread? Is it the "ANF/GNF" pcb? If so, is that a noise filter board, i.e., "automatic noise limiter/noise blanker/galaxy noise filter"?

Thx

[Shoebox223]

Yes..it is a noise filter...remove it and jump pin 2(input) to pin 4(output) with a piece of wire...had several of these go bad...that nf board didn't do much for noise anyway

http://www.cbtricks.com/radios/galaxy/d ... nf_pcb.htm

[smokinone]

What is the "NF board referred to in this thread? Is it the "ANF/GNF" pcb? If so, is that a noise filter board, i.e., "automatic noise limiter/noise blanker/galaxy noise filter"?

Thx

I think it means "Non Functional"

[222]

Hmmmm. Seems odd. I have always loved the 959 since its inception. I never noticed any issue such as this (at least not that i remember) & i have dealt w/many of them. (not disputing, just havent run into it). I'm sure i have checked the functionality & effectiveness of the anl/nb (cant remember at the moment if theyre both there, seperately, on this radio or lumped 2gether or just 1 of those 2?) & i never noticed anything that seemed any more or any less effective, in noise filtering ability, compared to say...a 29. I dont see how i couldve missed it, if the anl/nb part didnt work or wasnt worth its button. The gnl (which i always thought meant galaxy noise filter) always has seemed to be one of those "hi pass" or hi freq filters. I never liked its "effect" on the sound, but it also, seemed quite effective (regardless of liking or not).

So anyway, are u guys saying its a connection problem, where this board plugs in...?....or some other malfunction of the boards components? If its been tracked to simply a connection problem w/the pins or something, i would think such could somehow be corrected fairly easily, unless of course, you ARE saying that the boards' function is so bad and/or trouble prone, and/or ineffective (as far as noise filters go), that its not worth even fixing the connections & better to discard for a jumper? Wow, im really surprised if thats the case, and i would like to hear back about my above comments.

Merry merry happy happy

[smokinone]

Can't say what others are experiencing with this NF board, but mine was kicking in and out altering the output to the speaker. I could move it and the sound would come back, then it would go out again by itself. I removed it and put in the jumper now I have constant volume to the speaker. My connections were not the problem, but the module itself.

[222]

Thanx for the reply smokinone. I can understand how locating & removing the source of the problem was a positive, restoring good sound. But i am curious as to how u concluded that the boards connections were not the source of the intermittent sound, esp since u said someth to the effect of moving it (while its plugged in) resulted in the variable sound thing. In order for it to not be the connections, i would think it would have to be either a bad solder joint(s) somewhere on the board, or, even the rarity where a component has an internal intermittent, which certainly can be. Also, some of the electrical impulse noise that often gets into cb rx audio, can be real bad, very commonly...and most anl/nb circuits ive checked, against such noise, are usually VERY effective, often nearly eliminating that static, that comes on from so many sources...and so im curious if u were able to manipulate the board in such a way, that u could hear the level of effectiveness of the anl/nb, w/any significant electrical impulse noise present? I have developed a keen skill for "rooting out "intermittents" of all kinds & so this interests me for 1) where exactly is this intermittent (after all, it a great & very common radio w/a lg # in use & still being being made (i think), 2) what is the problem (if any) w/the effectiveness (or not) of the noise filters in this radio (aside from the intermittent issue) that would make some of you find it better to just discard it & make jumpers...i.e., are the working noise filters THAT POOR (performance-wise) that its not even worth finding/fixing the intermittent....and the radio gets left w/no noise filters at all? Or am i misunderstanding?.

Ho Ho Ho, hmmm hmm hmm..

[smokinone]

I wish I could help you with all the specifics, but I am as GREEN a radio tech as can be. I look to experts on this forum and others for guidance. I know a little about soldering, I can align a radio with the freq counter and use a scope in a limited fashion. This radio I'm working on was dead when I got it and by cleaning up some one elses bad solder joints and repairing some obvious damaged traces I was able to get it to receive. After that I checked the bias of the finals and found those to be bad and replaced them with the IRF520's as the originals were. Got that working. When I took the front part of the radio off to get to the 20-21-& 22 coils for PLL alignment is when I noticed the sound dropped by about half. Poking around the NF I found restored the sound. I pulled it out and checked the traces on the circuit board and they were all good, as the NF modules legs looked good as well. I found this thread about problems with the NF board and put in the jumper and problem solved. I did notice however that AM'ers keying on the channel (38 LSB) the radio exhibited a louder and more prominent squeel compared to my Jackson sitting next to it for comparison. It may or may not be linked to the NB/ANL circuit, I don't have that knowledge at this time. This radio has several problems I'm trying to work out before possibly turning it over to a PRO. I tinker and sometimes get lucky, sometimes not...OK, most times not, but I do learn something every time I get into any one of the radios I've played with.
Now the problem I have with this radio is no intelligible audio out on AM or SSB, although I have a SSB carrier of about 20 PEP watts. I replaced the 7222 chip as well with no luck. The Q54 & 55 seem OK as the voltages are correct in the SSB and AM modes. Now I am looking for more guidance on this issue.
I wish I could be of more help to you but I'm sure one of the guys here can explain the NF circuit more clearly.

[222]

Hey smokin....sorry if i misled you on my point(s), or maybe you just misunderstood the thrust of my post (prolly comb. of both..), but i wasnt questioning or even commenting on...your abilities, expertise level, how you went about anything, intentions, or any of the other points about the radio, etc etc....

All i was trying to say...and it is as much me trying to find out about this particular radio issue (orig posted about), as offering any opinion....is that i saw a post about an intermittent rx audio issue & the expert advice about the nf board elimination & jumpers. I didnt recognize, right off, what was an "nf" board, but i thought about & asked if reference was to noise filter & was told it was. So my concern then was twofold: 1) how did you determine it was the board itself rather than the board connections (based upon your words that said that, while at same time saying that moving the board had an effect) & 2) i was both trying to ask (anyone) if there is an inherent uselessness, or at least a poor performance level, of this particular radio models' noise filter circuits (aside from the audio fading/nf board problem), because my experience had shhown that w/o any doubt, most anl/nb circuits are very effective & very much needed & very much used.

With those 2 main points in mind, i was wondering how hard (or not) it might be to correct the problem, rather than eliminating the board for jumpers, and/or maybe somehow implimenting an alternative noise filter, if the board problem cant be fixed for some reason. And please understand that those concerns were about this radio in general & my finding out more specifics about the issue, not directed at you, per se, or any of the good work you are obviously doing. I mentioned that i had dealt w/many 959s & never come across this & so wanted to get to the bottom of whats the cause & how to fix, if possible.

The way i see it is, either the board has some inherent connection problem & if so, shouldnd be too hard to fix. Or, as you stated, it is not a connection problem but rather some problem w/the board itself. If thats indeed the case, then its a good question i posed, about how that determination was made. And if it is the board itself, then im not looking at 1 right at the moment, but i assume it couldnt have too many solder joints too go over & maybe there would be the fix. Otherwise, keeping in mind that we KNOW from the description (moving around) & the jumper fix, that it is indeed a connection problem SOMEWHERE, so if its on the board, but not an easily correctable solder joint, then maybe a faulty component internally (and if its a common problem, then maybe a bad batch of a particular component?). I have seen this a few times (internally intermittent). If that was the case, (doubtful, in my opinion) then i know some of the galaxy ppl & i can almost gaurantee you, regardless of age, that if such was identified as being the case, that galaxy would not only replace the part, but would also correct the production problem. I realize that the jumper thing is a quick & easy fix, but i dont think its the best idea if at the cost of an otherwise effective anl/nb circuit. If we were talking about something much less important & useful, like lets say a delta tune on an am radio, that was causing a similar kind of problem, i'd say fine, get rid of it as doesnt do nuch anyway & the majority of cb owners dont use it & most dont even know what it does. But anl/nb filtering is a must, in my opinion.

So my questions & concern is academic & about the issue, not you or your work.